The video seems to show William fixing his scarf - not aware Meghan is chatting to him.
One wrote on Twitter: "Maybe my imagination but William seemed to ignore Meghan.
"And William and Harry did not interact with each other much.
"Something just seemed off between them."
One fan mused, "Do William and Harry talk to each other? I feel there’s something wrong between them."
Another commented: "... it's sad William ignored Meghan's chatter as it looked like she said something to him."
While one royal fan observed, "They are always laughing and probably joking too but on this video they don't even look at each other.
"It's weird, I hope everything is okay between."
WATCH the royals at Sandringham
Prince William has reportedly clashed with his younger brother Harry over the past year with concerns that Meghan might not be a suitable with for his brother.
It is believed that William voiced his concerns to Harry as well as the Queen with his main concern being that of Harry and Meghan moving too quickly.
Previously, it had been rumoured that the main source of tension between the two royal couples stemmed from Meghan and Kate not getting along with each other.